/*
 * Copyright 2017, OpenSkywalking Organization All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Project repository: https://github.com/OpenSkywalking/skywalking
 */

package org.skywalking.apm.collector.stream.worker.impl.data;

import org.skywalking.apm.collector.core.cache.Window;
import org.skywalking.apm.collector.core.data.Data;

/**
 * 数据缓存
 *
 * @author peng-yongsheng
 */
public class DataCache extends Window<DataCollection> {

    /**
     * 写入的窗口数据
     */
    private DataCollection lockedDataCollection;

    @Override public DataCollection collectionInstance() {
        return new DataCollection();
    }

    /**
     * 根据 ID 判断 Data 是否存在
     *
     * @param id 编号
     * @return 是否存在
     */
    public boolean containsKey(String id) {
        return lockedDataCollection.containsKey(id);
    }

    /**
     * 根据 ID 获得 Data
     *
     * @param id 编号
     * @return Data
     */
    public Data get(String id) {
        return lockedDataCollection.get(id);
    }

    /**
     * 写入 Data
     *
     * @param id 编号
     * @param data Data
     */
    public void put(String id, Data data) {
        lockedDataCollection.put(id, data);
    }

    /**
     * 开始写入
     */
    public void writing() {
        lockedDataCollection = getCurrentAndWriting();
    }

    /**
     * 获得当前数据指向的数据数量
     *
     * @return 数量
     */
    public int currentCollectionSize() {
        return getCurrent().size();
    }

    /**
     * 完成写入
     */
    public void finishWriting() {
        lockedDataCollection.finishWriting();
        lockedDataCollection = null;
    }
}
